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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 0 |
| 4 | 96 |
| 5 | 320 |
| 6 | 3200 |
| 7 | 4480 |
| 8 | 14336 |
| 9 | 43008 |
| 10 | 122880 |
| 11 | 337920 |
| 12 | 901120 |
| 13 | 2342912 |
| 14 | 5963776 |
| 15 | 14909440 |
| 16 | 36700160 |
| 17 | 89128960 |
| 18 | 213909504 |
| 19 | 508035072 |
| 20 | 1195376640 |
| 21 | 2789212160 |
| 22 | 6459228160 |
| 23 | 14856224768 |
| 24 | 33957085184 |
[0,0,96,320,3200,4480,14336,43008,122880,337920, 901120,2342912,5963776,14909440,36700160,89128960, 213909504,508035072,1195376640,2789212160, 6459228160,14856224768,33957085184] |